With this rubber mold which has been either sprayed with mold release or coated with a thin layer of baby powder, molten wax is injected then the mold is carefully pulled apart and sequential, nearly identical wax positives are taken out. To make multiples in jewelry making what is usually done is a rubber mold is made from a positive metal piece using heat time and pressure. If you are making a ring, or something small like this you have it out of the mold and are inspecting it within 5 minutes of heating the metal to molten the process is quick. Yes the investment mold falls apart when you put it under running water or a large vessel of water which can be done about 30 seconds after the poured metal has hardened. now it needs to sit for about 10 - 15 undisturbed until it sets up, then it needs to sit for about 1.5 - 2 hours before you can start the burnout process in the kiln. if doing centrifugal casting, it can go over the top of the flask. With vacuum casting, you need to leave at least 1/8 of an inch at the top to aid in the suction during the casting. If there was a little bit of investment left over, after the time is up, pour the little bit on top. It bubbles up and over like an ancient tar pit! The rings were pretty small in this flask, so I didn't fill it up all the way to reduce the bubbling over. This removes air that might have been trapped around the waxes and still in the investment from pouring - vacuum for approx 1.5 minutes - don't go over your 8 minutes. I use a piece of chalk to write a number corresponding to the wax weights - the chalk doesn't burn off in the kiln so its easy to distinguish when getting them quickly. Now for the vacuuming of the flask! If you are vacuuming more than one flask of the same size, make sure to mark them.
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